Try-square.



UNITED STATES PATENT OFFICE.

DAVID FELIX BRODERICK. OF HARTFORD, CONNECTICUT, ASSIGNOR OF ONE-HALF TOLEWIS SPERRY, OF HARTFORD, CONNECTICUT.

TRY-SQUARE.

Ira-834,964.

Patented Nov. 6, 1906.

. Application filed March 'I, 1906. Serial No. 304.663-

To all whom it may concern:

Be it known that I, DAVID FELIx BROD- ERICK, a citizen of the UnitedStates, residing at Hartford, county of Hartford, State of Connecticut,have invented certain new and useful 1m rovements in Try-Squares, ofwhich the ollowing is a full, clear, and exact description.

My invention relates to improvements in measuring instruments-forexample, such as try-squares for carpenters, masons, and the liketheobject being to provide means in conjunction with the try-square topermit its use as a level or plumb, with which may also be ascertainedangles of inclination in perpendiculars and horizontals. I

The particular form of the invention shown in the drawings is such thatby a single means the operator may ascertain the angle of inclinationineither degrees or inches for a certain definite distance. I

In the drawings, Figure 1 is an elevation of my improved instrument.Fig. 2 is a detail sectional view. Fig. s-is a front elevation of adetail of construction detached. Fig. 4 is an edge view of said detail.

A is a try-square provided with the usual graduations along its edges.From one arm of the try-square is suspended a pendulous member having atits lower end a fan-like scale portion D. The pivot-stud C of the memberB is preferably fastened to it and adapted to be removably inserted in asocket or perforation in the square.

D. Along the E is a peep-hole through the fan portion lower edge of thepart D is a series of graduations reading away from a central zero-markU on the b0 y A ofthe try-square is an in exmark, (indicated at F,)whereby the angle of inclination in degrees may be read in connectionwith the graduated scale just described. Upon the body A of the squareis a scale having graduations "0, 1, 2, 3, 4, 5, 6, 5, 4, 3,2, 1, 0, thezeros being radially in line with the side edges of the extension D ofthe pivoted pendulum B when the parts are in the position shown. Whenthe lower edge of the s uare is rested on a surface which is inclinefrom the horizontal, the pendulum will swing to the right or left,according to the direction of inclination of the supportingsurface. Thenumber on the scale which is try-square, and thus in oppositedirections. These raduations indicate degrees.

opposite one of the radial side edges of the extension D undersuchcircumstances will indicate the inclination in terms of the ratios,say, of sixteenths of an inch of rise per running foot. If thesupporting-surface is inclined upward toward the left, the endulum willhang in a position'with itsle t-hand radial edge of the extension Dbeneath, say, 2, indicating that the inclination from the horizontal isat the rate of two-sixteenths or one-eighth of an inch per runningfootthat is, the tangent of the angle of inclination is +1 12=1=.O10416. Thesegraduations may be arranged in the same order as thegraduations on the lower scale and readable through the openin E on thefan-like portion D, and a central in ex-mark adjacent to the edge ofsaid peep-h le may be used to facilitate accurate reading.

The stud C has a thumb-head G. The washer H is screwed onto the stud andclamps the balls J, so as to afford a substantially frictionless bearingfor the member B. The inner end of the stud is reduced in diameter andscrews into a tapped hole in the body of the try-square, so that thependulous member may be readily attached or detached. The form of stud C(shown in Figs. 3 and 4) is intended to fit rather loosely in a hole inthe -try-square body. The lower end D is preferably rather heav to makethedevice more sensitive. The tfiicken'ed portion also helps to hold thelong shank away from the avoid friction.

The invention may be applied to a standard s uare. It serves all thepurposes of a spirit evel or plumb with the additional advantage ofgreater accuracy of reading.

What I claim, ters Patent, is

1. An instrument of the character described, comprising a body havingtwo flat and desire to secure by Let- I arms at right angles to eachother, with straight uninterrupted inner and outer side- 2. In anlnstrument of the character dea heavy fan-like I a scale thereon, athumb-screw passing through said bar at the opposite end, a washeradjustable thereon, a series of balls arranged between said washer andthe head of said screw and forming a bearing for said bar, said screwtaking into the perforation in said square.

DAVID FELIX BRODERICK.

Witnesses:

DENNIS F. BROWN, HARRY W. REYNOLDS.

